Aggressive behavior is a leading worldwide public health problem costing tens to hundreds of billions of dollars annually in terms of medical care and lost productivity. The human cost is equally great, creating distress and suffering in the aggressor, their victim, loved ones and society as a whole. Despite this there are currently no empirically supported treatments for pathological affective (hostile) aggression. A rich literature suggests that aggression is associated with impaired socio-emotional information processing, which is governed by a prefrontal-limbic circuit in the brain. This is supported by studies of affectively aggressive subjects showing increased amygdala response and decreased orbitomedial prefrontal response to negative socio-emotional stimuli such as angry facial expressions or negative evocative pictures. A goal of cognitive behavioral therapy is to reduce dysfunctional socio- emotional information processing. Preliminary data by the PI suggests a 12- session cognitive behavioral aggression treatment may be efficacious in reducing aggressive behavior and underlying cognitive (socio-emotional information processing) and biological (cortico-limbic activation) deficits associated with affective aggression. To assess the efficacy of this treatment, 120 subjects with clinically relevant affective aggression would be randomized to either the cognitive-behavioral aggression treatment or a supportive psychotherapy control. All subjects will monitor their aggressive behavior throughout the active treatment phase using ecological momentary assessment (EMA). Subjects would also complete self-report and behavioral of both aggression and social-emotional information processing and pre-treatment and post-treatment, then again at 6-month and 1-year follow-up. To assess the effect of the cognitive behavioral treatment on cortico-limbic functioning, subjects would complete two social information processing tasks (identifying the emotional valence of faces and evocative pictures) while undergoing functional Magnetic Resonance Imaging (fMRI) at pre-treatment and again at post- treatment. It is hypothesized that relative to supportive psychotherapy, the cognitive behavioral aggression treatment will result in decreased aggressive behavior and improved socio- emotional information processing as well as decreased amygdala/increased orbitomedial prefrontal activation to socio-emotional stimuli.